Ginger is a nutritional powerhouse, loaded with antioxidants, anti-inflammatory compounds, and other beneficial plant compounds. Some people enjoy eating raw ginger, while others prefer to cook with it by adding it to stir fries, soups, and baked goods. This leads to the question – does ginger lose nutrients when heated? In this article, we’ll explore what happens to ginger when it’s heated and whether cooking impacts its nutritional value.
The Nutrients in Raw Ginger
First, let’s take a look at the key nutrients found in raw, unpeeled ginger:
| Nutrient | Per 100g Raw Ginger |
|---|---|
| Calories | 80 |
| Protein | 1.82g |
| Fat | 0.75g |
| Carbs | 17.77g |
| Fiber | 2g |
| Vitamin C | 5mg |
| Vitamin B6 | 0.16mg |
| Iron | 0.6mg |
| Potassium | 415mg |
| Magnesium | 43mg |
Ginger contains a small amount of calories and macronutrients like protein, carbs, and fat. It’s highest in the vitamins, minerals, and bioactive plant compounds that provide its health-promoting properties.
Gingerols – The Main Bioactive Compounds
The key bioactive components in ginger are the gingerols, which give fresh ginger its pungent, spicy kick. The most abundant gingerol is 6-gingerol, which has been extensively researched for its anti-inflammatory, antioxidant, anti-nausea, and pain-relieving effects.
Studies show 6-gingerol has anti-cancer properties and the ability to inhibit tumor growth. It may also protect brain function and help prevent Alzheimer’s disease and age-related cognitive decline.
What Happens to Gingerols During Heating?
When ginger is heated, the gingerols undergo a chemical transformation into shogaols and zingerone. This reaction is sometimes called the “gingerol thermogenesis”.
Specifically, 6-gingerol is converted to 6-shogaol when ginger is dried or cooked. This reaction occurs more rapidly at higher temperatures.
Although the profile of gingerols changes with heating, research indicates that the shogaols retain powerful medicinal properties. In fact, 6-shogaol is considered the most pungent and biologically active component of dried or cooked ginger.
Bioactive Compounds in Dried vs. Raw Ginger
| Compound | % in Raw Ginger | % in Dried Ginger |
|---|---|---|
| 6-Gingerol | 0.78% | 0.12% |
| 8-Gingerol | 1.35% | 0.08% |
| 10-Gingerol | 1.28% | 0.15% |
| 6-Shogaol | 0.85% | 2.29% |
| Zingerone | 0.00% | 0.82% |
This table compares the levels of active ginger compounds in raw versus dried, heated ginger. When ginger is dried, the gingerol content decreases while shogaol and zingerone levels increase dramatically.
Research on Gingerols vs. Shogaols
Although the profile of compounds changes when ginger is heated, research suggests that dried and cooked ginger retains its medicinal and antioxidant properties:
- A study found the chemopreventive effects of dried ginger extract were comparable to or greater than fresh ginger against cancer cell growth.
- Both fresh and heated ginger exhibit antioxidant activity and the ability to suppress free radicals.
- In rats with induced kidney damage, oral pre-treatment with heated ginger extract provided nephroprotective effects.
- The anti-inflammatory properties of heated 6-shogaol isolated from ginger were equivalent to raw 6-gingerol in cells.
- In mice with induced gastric ulcers, 6-shogaol demonstrated equal or greater antioxidant and anti-ulcer effects compared to 6-gingerol.
Overall, this research suggests that while the profile of active compounds changes with heating, dried and cooked ginger retains its medicinal and antioxidant properties.
Nutrient Retention During Cooking
In addition to the bioactive compounds like gingerols and shogaols, ginger contains many vitamins, minerals, and antioxidants. How well are these nutrients retained when ginger is heated?
Unfortunately, there are limited studies examining ginger nutrient changes during different cooking methods. However, we can make some educated guesses based on research into vitamin and mineral retention for other vegetables:
- B Vitamins: These water-soluble vitamins are susceptible to leaching out during boiling. Up to 60% of thiamin, niacin and other B vitamins can be lost when boiling vegetables.
- Vitamin C: Also water-soluble, vitamin C degrades quickly with heat exposure. Up to 50% of vitamin C can be lost after 10 minutes of cooking.
- Carotenoids: These antioxidant plant pigments are generally heat stable at lower cooking temperatures under 100°C (212°F).
- Minerals: Minerals like potassium, magnesium, and iron are stable and not degraded by heat alone.
Based on this, boiling ginger is likely to cause the greatest nutrient losses, while nutrients may be preserved in ginger added at the end of stir-frying and baking.
Best Cooking Methods for Preserving Nutrients
To get the most nutrients from ginger, use these nutrient-preserving cooking methods whenever possible:
- Use lower temperatures like simmering and stewing.
- Opt for shorter cook times.
- Cut ginger into larger pieces to reduce surface area exposure.
- Add ginger at the end of cooking instead of the beginning.
- Pair ginger with ingredients high in vitamin C to help retain its antioxidants.
- Use fresh ginger juice or raw grated ginger to retain the most gingerol content.
Should You Eat Ginger Raw?
Both raw and heated ginger offer health benefits, so enjoying ginger in a variety of forms can help diversify your phytonutrient intake. Here are some benefits of raw versus cooked ginger:
Benefits of raw ginger:
- Highest gingerol content
- Maximum vitamin C levels
- Enzymes intact for better digestion
- Can be juiced or added to smoothies
Benefits of cooked ginger:
- Increased shogaol content
- Improved bioavailability and absorption
- Softens texture for easier chewing
- Intensifies flavor
For the best of both worlds, use fresh ginger at the end of cooking or in unheated recipes like dressings and smoothies. This ensures you’ll get both the raw gingerol compounds along with the shogaols that form during heating.
Conclusion
Ginger remains a nutritional powerhouse whether raw or cooked. Although the profile of bioactive compounds changes with heating, research shows cooked ginger retains its medicinal properties and antioxidant activity. Some nutrient loss occurs when ginger is boiled or overcooked, but lower temperatures help preserve nutrients. Enjoying both fresh and dried ginger can provide a diversity of gingerol and shogaol compounds and their associated health benefits.
